Pneumatic conveyor systems are extensively utilized in drive-in banking facilities to transport money, checks and other documents in a tubular container which moves through a pneumatic tube extending between a customer's station at a location spaced from the bank building and a cashier's station within the bank building. The pneumatic tube can provide a path which includes numerous legs extending in various directions, both horizontal and vertical. This is particularly advantageous in providing great flexibility in locating either the customer's station or the cashier's station. The pneumatic conveyor systems have generally been satisfactory where the material being transported comprises only checks, deposit slips, paper currency, or other light weight paper documents. However, the transport of heavy articles, e.g., rolls of coins, in such pneumatic conveyor systems can present a problem in that, unless restraining material is included in the tubular container, the articles can move about within the tubular container and thus are free to crash against the forward end of the tubular container when the tubular container changes from a horizontal portion of the conveyor run to a vertical portion of the conveyor run. Such impacts can damage the tubular containers as well as interfere with the smooth movement of the tubular container through the pneumatic conveyor.
While mechanical conveyors, driven by chains, cables or drive tapes, can generally handle heavier loads than the pneumatic conveyor systems, in general they are still subject to the problems of load shifting, particularly upon the transition from a horizontal leg to a vertical leg of the conveyor run. Bavis, U.S. Pat. No. 4,957,188, describes one effort to provide a stabilized carrier for use in conveying food and beverage containers between a processing station in a drive-in restaurant and a customer at a delivery station located remotely from the restaurant. The conveyor has a pair of drive tapes which are horizontally spaced apart from each other and which are driven in unison by a common drive. The carrier basket is suspended from the pair of conveyor drive tapes by mounting blocks and is free to rotate relative to the horizontal axis through the mounting blocks. A stabilizing cam is provided on the carrier basket in engagement with a cam track so as to prevent rocking of the carrier basket. Thus, the carrier basket will remain vertically disposed as the drive tapes translate between the horizontal and vertical flights of the conveyor, provided that all of the flights of the conveyor are located in a single vertical plane. The drive tapes are flexible and can bend to negotiate curves by being guided in a channel or other guiding device. Thus, with the carrier basket being suspended from the horizontally spaced apart pair of drive tapes, the conveyor can readily negotiate the transitions from the vertical to the horizontal and from the horizontal to the vertical. However, the conveyor system is not adapted to provide a transition from one horizontal direction to another horizontal direction, thereby limiting the usefulness of the conveyor system to a planar path.
Bavis, U.S. Pat. No. 5,054,605, discloses a conveyor system utilizing either a single drive tape or a pair of drive tapes, with each tape being connected to a rigid carrier by two connectors spaced apart along the longitudinal length of the carrier, with at least one of the connectors comprising a pin in a slot in order to permit a limited movement of the adjacent portion of the tape with respect to the rigid carrier. This permits accommodation of the increase in longitudinal length of tape between the two attachment points when the carrier passes through a planar transition curve between a horizontal leg and a vertical leg due to the curvature of the tape.
Although U.S. Pat. No. 5,054,605 acknowledges that several prior conveyor systems were designed for conveying items which must remain vertically oriented throughout the conveying movements, such as liquid containers, food items, and the like, the apparatus disclosed in U.S. Pat. No. 5,054,605 is not capable of accomplishing that objective in any conveyor system which provides movement in any direction other than a single horizontal straight line or a single vertical straight line. Whether a pair of drive tapes or a single drive tape is employed, the carriage is positioned vertically with its first end up at the customer station and vertically with its first end down at the teller station, while being in a horizontal position for a portion of the distance between the two stations. Thus, any object placed in the carriage in a right-side-up position in one station would be upsidedown in the other station. Moreover, even though the patent acknowledges that the flexible drive tape is capable of assuming an almost unlimited variety of curves, bends and substantially straight sections, the only disclosed conveyor paths are planar paths and the disclosed apparatus is not suited for conveyor paths having transition curves in different planes.